diff options
author | Samuel Holland <samuel@sholland.org> | 2020-10-22 05:12:16 +0300 |
---|---|---|
committer | Jagan Teki <jagan@amarulasolutions.com> | 2020-10-22 09:13:43 +0300 |
commit | e72a6be4fc071930016903638e1e493ab5d3be8a (patch) | |
tree | e9f81dae2d026188ec7edc378dfe2219abf9c868 /board/sunxi/README.sunxi64 | |
parent | 18bd45592cbd87a766450d08169ec574853b50fa (diff) | |
download | u-boot-e72a6be4fc071930016903638e1e493ab5d3be8a.tar.xz |
sunxi: binman: Add support for including SCP firmware
Allwinner sun50i SoCs contain an OpenRISC 1000 CPU that functions as a
System Control Processor, or SCP. ARM Trusted Firmware (ATF)
communicates with the SCP over SCPI to implement the PSCI system
suspend, shutdown and reset functionality. Currently, SCP firmware is
optional; the system will boot and run without it, but system suspend
will be unavailable.
Since all communication with the SCP is mediated by ATF, the only thing
U-Boot needs to do is load the firmware into SRAM. The SCP firmware
occupies the last 16KiB of SRAM A2, immediately following ATF.
Reviewed-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Samuel Holland <samuel@sholland.org>
Reviewed-by: Jagan Teki <jagan@amarulasolutions.com>
Diffstat (limited to 'board/sunxi/README.sunxi64')
-rw-r--r-- | board/sunxi/README.sunxi64 | 47 |
1 files changed, 40 insertions, 7 deletions
diff --git a/board/sunxi/README.sunxi64 b/board/sunxi/README.sunxi64 index 258921af22..4803bc9ff2 100644 --- a/board/sunxi/README.sunxi64 +++ b/board/sunxi/README.sunxi64 @@ -14,8 +14,12 @@ Quick Start / Overview - Build the ARM Trusted Firmware binary (see "ARM Trusted Firmware (ATF)" below) $ cd /src/arm-trusted-firmware $ make PLAT=sun50i_a64 DEBUG=1 bl31 +- Build the SCP firmware binary (see "SCP firmware (Crust)" below) + $ cd /src/crust + $ make pine64_plus_defconfig && make -j5 scp - Build U-Boot (see "SPL/U-Boot" below) $ export BL31=/path/to/bl31.bin + $ export SCP=/src/crust/build/scp/scp.bin $ make pine64_plus_defconfig && make -j5 - Transfer to an uSD card (see "microSD card" below) $ dd if=u-boot-sunxi-with-spl.bin of=/dev/sdx bs=8k seek=1 @@ -24,13 +28,17 @@ Quick Start / Overview Building the firmware ===================== -The Allwinner A64/H5 firmware consists of three parts: U-Boot's SPL, an -ARM Trusted Firmware (ATF) build and the U-Boot proper. -The SPL will load both ATF and U-Boot proper along with the right device -tree blob (.dtb) and will pass execution to ATF (in EL3), which in turn will -drop into the U-Boot proper (in EL2). -As the ATF binary will become part of the U-Boot image file, you will need -to build it first. +The Allwinner A64/H5/H6 firmware consists of several parts: U-Boot's SPL, +ARM Trusted Firmware (ATF), optional System Control Processor (SCP) firmware +(e.g. Crust), and the U-Boot proper. + +The SPL will load all of the other firmware binaries into RAM, along with the +right device tree blob (.dtb), and will pass execution to ATF (in EL3). If SCP +firmware was loaded, ATF will power on the SCP and wait for it to boot. +ATF will then drop into U-Boot proper (in EL2). + +As the ATF binary and SCP firmware will become part of the U-Boot image file, +you will need to build them first. ARM Trusted Firmware (ATF) ---------------------------- @@ -53,6 +61,31 @@ As sometimes the ATF build process is a bit picky about the toolchain used, or if you can't be bothered with building ATF, there are known working binaries in the firmware repository[3], purely for convenience reasons. + SCP firmware (Crust) +---------------------- +SCP firmware is responsible for implementing system suspend/resume, and (on +boards without a PMIC) soft poweroff/on. ATF contains fallback code for CPU +power control, so SCP firmware is optional if you don't need either of these +features. It runs on the AR100, with is an or1k CPU, not ARM, so it needs a +different cross toolchain. + +There is one SCP firmware implementation currently available, Crust: +$ git clone https://github.com/crust-firmware/crust +$ cd crust +$ export CROSS_COMPILE=or1k-linux-musl- +$ make pine64_plus_defconfig +$ make scp + +The same configuration generally works on any board with the same SoC (A64, H5, +or H6), so if there is no config for your board, use one for a similar board. + +Like for ATF, U-Boot finds the SCP firmware binary via an environment variable: +$ export SCP=/src/crust/build/scp/scp.bin + +If you do not want to use SCP firmware, you can silence the warning from binman +by pointing it to an empty file: +$ export SCP=/dev/null + SPL/U-Boot ------------ Both U-Boot proper and the SPL are using the 64-bit mode. As the boot ROM |